Compilare: user.cpp: In function ‘int main()’: user.cpp:5:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("mafia.in", "r", stdin); ^ user.cpp:6:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("mafia.out", "w", stdout); ^ user.cpp:12:17: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &T); ^ user.cpp:17:32: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%lld%d", &N, &M, &X); ^ user.cpp:19:22: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &elem); ^ user.cpp:25:20: warning: ‘num’ may be used uninitialized in this function [-Wmaybe-uninitialized] rest = suma - num; ^